The human immune system is a potentially powerful line of defense against cancer. Many biological obstacles exist in cancer patients that thwart tumor-specific T cell expansion, activation, tumor trafficking and killing. Among these is inadequate T cell precursor frequency and low T cell receptor (TCR) binding affinity for tumor antigen. Our hypothesis is that transplantation of high affinity TCR-transduced stem cells will create in the recipient an engineered immune system with potent antitumor biology. Thus, the single goal of this Program Project Grant (PPG) is to test this hypothesis by attempting to control or cure metastatic melanoma. This application is a key part of the strategy to arise from a 3-year collaboration among a score of investigators from four research universities (Caltech, UCLA, USC, UCONN) representing 4 cancer centers, 2 gene medicine programs, 13 departments and several institutes. Our research group will converge the disciplines of immunology, genetic engineering, stem ceil biology, virology, biological imaging and human gene medicine to engineer a tumor-specific human immune system. This will be accomplished in a PPG with 5 projects supported by 3 cores. The PPG will: (1) undertake two first-in-human clinical investigations in which a MART-1 melanoma antigen TCR will be introduced into T cells and hematopoietic stem cells using a lentiviral vector also expressing a PET reporter allowing serial noninvasive imaging of the development of an engineered immune system, (2) fundamental studies of the biology of TCR engineered hematopoietic and embryonic stem cells, and (3) basic biology of TCR engineering. State of the art cores in cell and gene therapy, immunological monitoring and biological imaging will support this science. In this PPG, basic and clinical science will be conducted in parallel, each informing the other;basic scientists and physician-scientists will work together as a team to develop discovery-based science that will change the care of patients.